Boat engine cooling system

ABSTRACT

The boat engine cooling system provides cooling of the engine of a boat or other nautical vehicle through both chemical coolant, such as an antifreeze solution, and environmental water; i.e., the water the vehicle is passing through. In use, heated engine coolant is expelled by the engine and passes through a coolant inlet port formed through a hollow tank, where it is transported through a coolant pipe to the engine. Further, water from the environment (i.e., the lake, ocean or other body of water the vehicle is passing through) is injected into a cooling reservoir in the hollow tank through a water inlet port. The engine coolant passing through a central portion of the coolant pipe is cooled by the water in the cooling reservoir prior to circulating back through the engine.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/129,390, filed Jun. 23, 2008.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to inboard motors for boats, andparticularly to a boat engine cooling system for an inboard motor.

2. Description of the Related Art

Typical inboard boat motors operate at temperatures of approximately180° F. It is well known in the art to use the environmental water(i.e., the water of the lake, ocean or other body of water the boat istraveling in) to cool the engine, with this water being passed into oraround the engine in a conventional manner.

However, such systems rely on pure water for the cooling of the engine.Due to contaminants, such as chemical pollutants, as well as naturalmarine life, filter systems must be used before the water is passed tothe engine. Such filters must be changed regularly, can easily becomeclogged, and are not 100% effective, thus resulting in clogged engines,broken blocks and the like, which must be fixed or replaced. Further,environmental laws of some jurisdictions have required this type ofsystem to be banned, since the water passing through the engine and backinto the environment may be contaminated by the engine. It would bedesirable to cool the engine of the boat with environmental water, butwithout the risk of contaminating either the environment or the engine.Thus, a boat engine cooling system solving the aforementioned problemsis desired.

SUMMARY OF THE INVENTION

The boat engine cooling system provides cooling of the engine of a boator other nautical craft through injection of both chemical enginecoolant, such as antifreeze, and environmental water i.e., the water thevehicle is passing through. The boat engine cooling system includes ahollow tank adapted for mounting within the boat or other vehicle. Thehollow tank defines an open interior region therein. An engine coolantinlet port, an engine coolant outlet port, a water inlet port and atleast one water outlet port are all formed through an outer wall of thehollow tank.

A partition wall is mounted within the hollow tank. The partition walldivides the open interior region of the hollow tank into a coolingregion and an inner tank. The partition wall has a passage formedtherethrough.

Both the hollow tank and a boat engine are mounted to the boat (or othernautical craft) in a conventional manner, with the engine being in fluidcommunication with the hollow tank. A coolant pipe having opposed firstand second ends extends into the hollow tank. The first end of thecoolant pipe is joined to the coolant inlet port, and a central portionof the coolant pipe extends within the cooling region of the hollowtank. The coolant pipe passes through the passage formed through thepartitioning wall, and the second end thereof terminates in a spout, forinjecting cooled engine coolant into the inner tank.

In use, heated engine coolant passes through the coolant inlet port andis transported through the coolant pipe to the inner tank, and then outof the inner tank and back to the engine for circulation through coolantpassages defined in the engine. Further, water from the environment(i.e., the lake, ocean or other body of water the vehicle is passingthrough) is injected into the cooling region of the hollow tank throughthe water inlet port. The engine coolant passing through the centralportion of the coolant pipe is cooled by heat transfer with the water inthe cooling region of the hollow tank prior to transport thereof to theengine.

These and other features of the present invention will become readilyapparent upon further review of the following specification anddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The sole FIGURE is a diagrammatic side view of the boat engine coolingsystem according to the present invention.

Similar reference characters denote corresponding features consistentlythroughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The boat engine cooling system 10 provides cooling of the engine 16 of aboat or other nautical craft through injection of both chemical enginecoolant, such as antifreeze, and environmental water; i.e., the waterthe boat is passing through. The boat engine cooling system ispreferably applied to an inboard engine 16. It should be understood thatthe system 10 and engine 16 shown in the sole drawing FIGURE may be usedwith any type of marine propulsion system, whether an inboard oroutboard engine.

The boat engine cooling system 10 includes a hollow tank 14. As shown inthe drawing, the hollow tank 14 defines a reservoir. Hollow tank 14 ismounted within or on the boat and is connected to the boat engine 16, aswill be described below in greater detail. An engine coolant inlet port24, an engine coolant outlet port 30, a water inlet port 36 and a pairof water outlet ports 41, 42 are all formed through an outer wall 15 ofthe hollow tank 14. A pressure relief port 32 may also be formed throughouter wall 15 adjacent inner tank 19, and may be releasably covered by acap or other seal 34. Hollow tank 14 may have any desired shape anddimensions. Exemplary dimensions for the cylindrical tank shown in thedrawing are a length of approximately nineteen inches and a diameter ofbetween approximately ten and twelve inches.

A bulkhead or partition 20 divides the open interior region of thehollow tank 14 into a cooling reservoir 17 and an inner tank 19.Partition wall 20 is shown for exemplary purposes only. It should beunderstood that the size, shape, and location of partition wall 20depend upon the size and contouring of outer tank 14. Partition wall 20has a passage 28 formed therethrough, as will be described in greaterdetail below. Further, as will be described in greater detail below,partition wall 20 maintains a fluid-tight compartment 19 for receivingengine coolant 23.

As shown, a coolant pipe 26 extends through the hollow tank 14. In theFIGURE, the coolant pipe 26 is shown as a substantially serpentine coil,although coolant pipe 26 may have any shape that maximizes the surfacearea of pipe 26 exposed within the hollow tank 14 for heat exchange.Coolant pipe 26 is formed from a thermally conductive material, such asaluminum.

The coolant pipe 26 is joined to coolant inlet port 24 and extendswithin the cooling reservoir 17 of the hollow tank 14, as shown. Thecoolant pipe 26 passes through the passage 28 formed through partitionwall 20 and terminates in a spout 50.

In use, heated engine coolant 22, which has been heated by boat engine16, passes through the coolant inlet port 24 and is transported throughthe coolant pipe 26 to the inner tank 19. Heated engine coolant 22 hasbeen heated during work within the boat engine 16 and is expelled underpressure by engine 16 through pipe 26. As will be described in furtherdetail below, the heated coolant 22 is cooled within region 17 of tank14, resulting in cooled engine coolant 23. Cooled engine coolant 23 isexpelled from pipe 26 through spout 50 to be collected within inner tank19. The cooled engine coolant 23 is drawn from inner tank 19 throughport 30 by engine 16 for usage therein. The engine coolant passesthrough a closed system, thus preventing contamination of the coolantthrough the cooling process. A coolant expansion tank 52 may further bemounted within the boat and is in fluid communication with inner tank 19through port 32. In the event of an excess volume of collected coolant,or excessive fluid pressure within inner tank 19, the excess coolant canbe vented through a pressure relief valve fitted in port 32 into thecoolant expansion tank 52.

Water 40 from the environment (i.e., the lake, ocean or other body ofwater the boat is passing through) is injected into the coolingreservoir 17 of the hollow tank 14 through the water inlet port 36.Water 40 is injected into cooling region 17 through line 38 and waterinlet port 36 by any suitable pressurized pump. The water 40 remainswithin cooling reservoir 17 and is not mixed with the engine coolant 22,23, thus allowing the engine 16 to remain free of contamination from theexternal water supply and preventing contamination from engine 16 intothe water supply.

The engine coolant 22 passing through coolant pipe 26 is cooled by heatexchange with water 40 in cooling reservoir 17 prior to transportthereof to the engine 16. Water 40 exits cooling region 17 through wateroutlet ports 41, 42 and lines 43, 44, respectively, and fresh,relatively cool water is drawn through line 38 and inlet port 36 toreplace it. Water is drawn through ports 41, 42 through the usage of anysuitable type of pump or the like. Typical boat motors equipped withcooling system 10 operate at temperatures of approximately 180° F. Theheated coolant 22 is expelled at approximately this temperature and isthen cooled by the environmental water 40 drawn into tank 14. Theenvironmental water is typically at a temperature of approximately 70°F.

It is to be understood that the present invention is not limited to theembodiment described above, but encompasses any and all embodimentswithin the scope of the following claims.

1. A boat engine cooling system, comprising: a hollow tank having anouter wall and an engine coolant inlet port, an engine coolant outletport, a water inlet port and at least one water outlet port formedthrough the outer wall; an inner wall mounted within said hollow tank,the inner wall dividing the hollow tank into a cooling reservoir and aninner tank, the inner wall having a passage formed therethrough, thecooling reservoir being in communication with the engine coolant inletport, the water inlet port and the at least one water outlet port, theinner tank being in communication with the engine coolant outlet port; acoolant pipe having an inlet extending into the tank through the enginecoolant inlet port and an outlet extending through the passage formedthrough the inner wall into the inner tank, the inlet of the coolantpipe and the engine coolant outlet port being adapted for attachment toa boat engine in order to circulate a chemical coolant through theengine, the coolant pipe being formed from a thermally conductivematerial and forming a heat exchange coil within the tank; means forpumping a chemical coolant through the coolant pipe; and means fordrawing cool water through the cooling reservoir; whereby the chemicalcoolant cools the engine and is itself cooled by heat exchange with coolwater in the cooling reservoir.
 2. The boat engine cooling system asrecited in claim 1, further comprising a pressure relief port formedthrough said hollow tank, the pressure relief port being incommunication with the inner tank.
 3. The boat engine cooling system asrecited in claim 2, further comprising a coolant expansion tankpositioned external to said hollow tank, the coolant expansion tankbeing in fluid communication with the pressure relief port.
 4. The boatengine cooling system as recited in claim 1, wherein said coolant pipehas a substantially serpentine contour.
 5. The boat engine coolingsystem as recited in claim 1, wherein the passage formed through saidinner wall is positioned above the engine coolant outlet port.
 6. Theboat engine cooling system as recited in claim 1, further comprisingmeans for expelling water from the cooling reservoir through the atleast one water outlet port.
 7. The boat engine cooling system asrecited in claim 1, wherein the water inlet port is formed through anupper portion of said hollow tank.
 8. The boat engine cooling system asrecited in claim 7, wherein the at least one water outlet port is formedthrough a lower portion of said hollow tank.
 9. The boat engine coolingsystem as recited in claim 8, further comprising a pressure relief portformed through the upper portion of said hollow tank, the pressurerelief port being in communication with the inner tank.
 10. The boatengine cooling system as recited in claim 9, further comprising acoolant expansion tank positioned external to said hollow tank, thecoolant expansion tank being in fluid communication with the pressurerelief port.
 11. A boat engine cooling system, comprising: a hollow tankhaving an outer wall and an engine coolant inlet port, an engine coolantoutlet port, a water inlet port and at least one water outlet portformed through the outer wall; an inner wall mounted within the hollowtank, the inner wall dividing the hollow tank into a cooling reservoirand an inner tank, the inner wall having a passage formed therethrough,the cooling reservoir being in communication with the engine coolantinlet port, the water inlet port and the at least one water outlet port,the inner tank being in communication with the engine coolant outletport; a coolant pipe having an inlet extending into the tank through theengine coolant inlet port and an outlet extending through the passageformed through the inner wall into the inner tank, the inlet of thecoolant pipe and the engine coolant outlet port being adapted forattachment to a boat engine in order to circulate a chemical coolantthrough the engine, the coolant pipe being formed from a thermallyconductive material and forming a heat exchange coil within the tank;means for pumping a chemical coolant through the coolant pipe; means fordrawing cool water through the cooling reservoir; and means forexpelling water from the cooling reservoir through the at least onewater outlet port; whereby the chemical coolant cools the engine and isitself cooled by heat exchange with cool water in the cooling reservoir.12. The boat engine cooling system as recited in claim 11, furthercomprising a pressure relief port formed through said hollow tank, thepressure relief port being in communication with the inner tank.
 13. Theboat engine cooling system as recited in claim 12, further comprising acoolant expansion tank positioned external to said hollow tank, thecoolant expansion tank being in fluid communication with the pressurerelief port.
 14. The boat engine cooling system as recited in claim 11,wherein said coolant pipe has a substantially serpentine contour. 15.The boat engine cooling system as recited in claim 11, wherein thepassage formed through said inner wall is positioned above the enginecoolant outlet port.
 16. The boat engine cooling system as recited inclaim 11, wherein the water inlet port is formed through an upperportion of said hollow tank.
 17. The boat engine cooling system asrecited in claim 16, wherein the at least one water outlet port isformed through a lower portion of said hollow tank.
 18. The boat enginecooling system as recited in claim 17, further comprising a pressurerelief port formed through the upper portion of said hollow tank, thepressure relief port being in communication with the inner tank.
 19. Theboat engine cooling system as recited in claim 18, further comprising acoolant expansion tank positioned external to said hollow tank, thecoolant expansion tank being in fluid communication with the pressurerelief port.
 20. A boat engine cooling system, comprising: a hollow tankhaving an outer wall and an engine coolant inlet port, an engine coolantoutlet port, a water inlet port and at least one water outlet portformed through the outer wall, the tank forming a cooling reservoir; acoolant pipe having an inlet extending into the tank and an outletextending from the tank, the inlet and the outlet being adapted forattachment to a boat engine in order to circulate a chemical coolantthrough the engine, the coolant pipe being formed from a thermallyconductive material and forming a heat exchange coil within the tank;means for pumping a chemical coolant through the coolant pipe; and meansfor drawing cool water through the cooling reservoir; wherein thechemical coolant cools the engine and is itself cooled by heat exchangewith cool water in the cooling reservoir.